Grinding compound filter and method of operation



0a. 31, 1933. R A, T R HAL 1,932,996

GRINDING COMPOUND FILTER AND METHOD OF OPERATION Filed Nov. 21, 1932 27 INVENTOR5 30 5| Rudd 677 A. h aiz ez'zs 7722/6 Ajorczz 60/1 23 ay m 9 ay ATTORNEY6 Patented Oct. 31, 1933 GRINDING COMPOUND FILTER "AND METHOD OF OPERATION Rudolph A. Walters and Niels A. Sorenson, Fostoria, Ohio Application November 21, 1932 Serial No. 643,598

Claims.

The present invention relates to an improvement in the treatment of compound solutions which are used in grinding-and abrading proc esses. Inasmuch as an abrading process results 5 in the production of very fine, small particles of metal as well as abrasive, it is of utmost importance that the liquid grinding compound be kept clean and free from such particleswhich. are held in suspension and flotation. There as a forty-four (44) per cent saving in grindingwheel cost, a substantial economy in wheel dressing and diamond dresser expense, and finally results in the eliminationof scratches and irregularities in the abrading work, thereby-permitting the use of a finer grit wheel.

It is therefore the general" object and natureof' this invention to produce a grinding compound filter, together with a novel method of the operation of the same in which there are no mechanical parts readily subject to rust and wear deterioration; a filter which "is of simple and durable construction and which may be quickly and convenientlyinstalled on any abradingapparatus. To the accomplishment of the foregoing and related ends, said invention, then,"

consists of the means hereinafter fully described and particularly pointed out in the claims.

The annexed drawing and the'followin'g de scription set forth' ln detail certain means and one mode of carryingout the invention, such disclosed means and mode illustrating, however, but one of various ways in which the-principle of the invention may be used.

In said annexed drawing: I

Fig. 1 is a half sectioned elevational view takenthrough the central elevational' plane of the apparatus constructed according to the principle of our invention; Figs. 2 and 3 are plan views upon a smaller'scale than that of Fig. 1 and illustrative of the mode of operation.

Now referring more particularly to the drawing, the ,filter body proper is composed of an integral unit casting designated generally by the numeral 1 in which there are found essentially the spherical filtering chamber 2, having the inlet openings 3 and outlet opening 4 and the by-pass chamber 5. The upper end of theby pass chamber 5 has theopening 6 communicating with and immediately adjacent theputlet opening 4. Thelower end of the by-pass chamber 5 has the opening '7 which commun cates with the valve which shall be subsequently described. I

The interior of the filtering chamber 2 and ofthe-by-pass chamber 5 are occupied by a;fil-. tration medium 8 composed of a coarse-fibrous; resilient materiaL; Commercial horsehair has been, found to be the filtering inaterialbest adapted to be utilized with our device.- Such a material possesses the necessary resilience and fibrous structure so that there is in BITQCUDIQ-g vided a vast surface over which the grinding, 7 compound might flow and to which the fine minute particles of suspension willadhere while at the same time presenting minimum resistance to. the, flow of the-liquid compound. The inherent resilience of the. horsehair prevents thea7 filtration medium from becoming packed and solid] and thereby impeding the passage of the grinding solution. Furthermore, if one of the horsehair fibres should by chance, become included. in the solution passing through. to the grinding wheel, it-will not injure or scratch the grinding work, since it is comparatively soft and willpass easily thereover without-having any damaging effect.

A perforated metallic plate or screen 9 is posi 35 tioned in the outlet opening 4 as added assurance against the inclusion of a hair fibre from the filtering medium 8 in the liquidgrinding solution, Similarly, a screen 10-is positioned in the inlet opening 3. A shaft 11 is journaledcentrally of the filtering chamber 2 on its inner end-by the bearing 12 and on its outer-fend by. the bearing 13. V The bearing 13 is, in turn, found to be in the removable cover plate 14 secured to the body of the housinglby suitable fastening studs 15. r The outer end 16 of the shaft 11 extends exteriorly-of the filter chamber 2 and is slightly flattened for the reception of an actuating tool, which shall be later referred to. A threaded bushingl'l, bearing against the packing18, constitutes a packing gland for sealing the interior of the filter chamf her 2. p 1

A removable cover plate 19 is secured to the exterior wall of the by-pass chamber 5 by means of the fastening nuts 20. A gasket 21 may be interposed between the cover plate 19 and the face of the by-pass chamber 5 for the purpose of effecting an efficient liquid seal. ,The removal of the cover plate 19 affords access to the interior of the by-pass chamber 5 for cleaning and inspection when found necessary, as well as for installation and removal of the filtration medium 8.

A pair of rods 22 are mounted upon and extend radially from the shaft 11, and are adapted to engage with the body of the filtration mediumB. Similarly a pair of rods 23 may be positioned in the shaft 11 in a plane normal to that of the rods 22.

A valve housing 24 is attached to the lower side of the main housing 1 by means of fastening nuts 24. This valve housing 24 includes the passage 25 leading from the lower end 7 of the by-pass chamber 5, the passage 26 communicating with the filter chamber inlet 3, the flushing outlet 27 and the supply inlet 28. The above enumerated valve passages 25, 26, 2'7 and 28 converge at a common point wherein there is positioned the rotatable valve plug 29. of passages 30 and 31 which are so constructed as to effect, at one position of the plug 29, communication between the passages 25 and 28 and 26 and 27, respectively; and at another position,

4 communication between passages 26 and 28 only.

' gage the flattened end 16 of the shaft 11.

The'outer end of the outlet opening 4 is in the formof an interiorly threaded flange 32 to which there is connected the'fiexible hose or conduit 33 leading to the nozzle adapter 34. The nozzle 34 is positioned adjacent the grinding wheel where the abrading action occurs. A valve 35, mounted above the nozzle 34 is for the purpose of closing the hose 33. i

- An operating tool 36, has a wrench opening '38 in one end which is adapted to fit over and en- The tool 36 has another wrench opening 37 which is adapted to'engage with the outer end of the valve plug 29.

Having above described these structural features of our device, the mode of operation shall next be considered. The liquid grinding compound solution which is usually composed' of an emulsion of oil, water and commercial soda is fed from a. pump throughthe pipe 40 to the valve 24; Under normal'operating conditions the valve is in the position as indicated in Fig. 3' in which the grinding compound is forced directly through the body of the filtration medium 8 in the chamber 2 and out through the outlet 4, through the conduit 33 and'to the nozzle 34. Under average operating conditions the filter should be flushed only about once every five hours. The flushing operation necessitates only two minutes and'invalves turning the valve plug 29 to the pos'ition shown in Fig. 2, while simultaneously closing the valve 85. In this position the compound will travel through theby-pa'ss chamber 5 and reverse its direction of fiow down'through the filtration medium 8 and out through the'valve'outlet 2'! and pipe 41 to the'drain. While this flushing operation is taking place, the actuating tool 36 is removed from the valve plug stem 29 and en-'- gaged with the end 16 of the shaft 11; where it is moved back'and forth through an angle of about 66". This latter oscillation of theshaft 11 pro: duces an agitation 'of the filter medium 8 in the chamber 2 which tends to loosen the fine particles of "suspension whichhave been removed from the grinding solution and have adhered to the hair fibres. The reversal of thefiow of the liquid through the filtration medium, combined through the by-pass chamber 5 and the filtering The plug 29 has a pair ly be thrown back to the position shown in Fig. 3 and the grinding compound filtration process continued. Although a flushing fluid, such as Water, from another source may be directed chamber 2, in order to render the installation and operation of our device as simple and efiicient as possible, it is preferred that the grinding compound itself be used as a fiushing fluid. In which case, it is found most feasible to make the by-pass chamber 5 a filtering chamber also in order that no dirt and grit will be deposited on the top of the filtering chamber 2 and subsequently carried over to the grinding wheel. In other words, during the flushing operation, the grinding compound is initially filtered and cleaned, before it is allowed to perform its flushing function.

It is to be further remarked that the filtering chamber 2 in its preferred embodiment takes a spherical or globular form. This latter expedient is for the purpose of effecting the maximum volume of filtering medium to be contained within the "minimum area of enclosing surface. The spherical form of the chamber further insures a thorough circulation. of the liquid solution 1C1 through the filtering medium, there being no pockets or'recesses which might serve as dead spaces through which the solution would not efficiently flow. The spherical form of the filtering chamber also permits greater effectiveness of the agitating action, inasmuch as the entire mass of the filtering medium 8 is free to move with respect 'to its containing walls, and every portion of the filtering medium body can be equally well agitated. H0

The preceding description will make it apparent that We have employedran entirely different method in filtering grinding compounds and analogous fluids in that'the filtering medium which may be horse hair isfirstcoated by the flow of liquid in one direction upon surfaces thereof that face in acommon direction. For ex ample,by reference to Fig. 1 it will be seen that as the l-iquidfiows upwardly through the'filtering 1") medium-8 the downwardly facing surfaces willl20 first become coated with the fine particlesof the grinding solution. Thengwhen it is desired to, clean the filter "we rotate the filtering medium so as to expose the coated surfaces thereof to the action of the flushing fluid which is passed through the bypass 5. Obviously, the combined action ofrotating and reversing the flow will result in a thorough cleansing of the filter. While we recognize that'it is old to reverse the flow in a filter, we do not believe that it is old to rotate the filtering medium so astoexpose different portions thereof to the action of the grinding compound during its travel through the filter. Furthermore, it is thought that we are the first to bodily rotate as distinguished from'mere ag-ita tion to present different surfaces to the flow :of grinding compound.

.It is alsocontemplated that ourabove described filterJ-may equally Well-be used for the removal of fine particles of suspension and flotation from liquids other than grinding compounds; such as lubricating oils which are circulated through an internal combustion engine and thereby entrain fine particles of carbonand foreign matter.

Other modes of applying the principle of our invention may be employed instead of the one explained, change being made as regards the means and the steps herein disclosed, provided those stated by any of the following claims or their equivalent be employed.

We therefore particularly point out and distinctly claim as our invention:

1'..In a device. of the character described, the combination of a chamber, inlet and outlet openings insaid chamber, a filtration medium of relatively coarse, resilient, fibrous material occupying the interior of said chamber and forming a unitary mass through which a grinding compound may flow, and meansfor bodily; moving such filtration medium asa' unit, whereby different surfaces thereof may be successively presented to the flow of-said compound; w

In a device ofthe character described, the combination of a spherical chamber, inlet and outlet .openings in said chamber, a; filtration medium of .relatively coarse, resilient, fibrous material occupyingthe interior :of said chamber and forming a unitary mass through whicha grinding compound may flow, and means for oscillating said filtration medium with respect to said chamber as a unit whereby different surfaces thereof may be successively presented to the flow of said compound.

3. In a device of the character described, a

; housing member composed of a filtering chamber,

" combination of a housing member composed of a spherical filtering chamber, inlet and outlet openings communicating with said chamber, a bypass chamber leading between said first-named chamber and around said openings, a filtration medium of relatively coarse, resilient, fibrous material occupying the interior of said filtering chamber and forming a unitary mass through which a grinding compound may flow, and means for oscillating said filtration medium with respect to said chamber.

' said first-named 5. In a device of the character described, a housing member composed of a filtering chamber, inlet and outlet openings communicating with said chamber, a by-pass chamber leading around chamber openings, a second outlet opening positioned adjacent said inlet opening, a three-way valve positioned at the juncture of said by-pass chamber,

- said inlet opening and said second outlet opening, and a filtration medium of relatively coarse, re-

silient, fibrous material occupying the interior of said filtering chamber.

6. In a device of the character described, a

housing member composed of a filtering chamber, inlet and outlet openings communicating with said chamber, a by-pass chamber leading around said first-named chamber and between said openings, a second outlet opening positioned adjacent said inlet opening, a three-way "valve positioned at the junctureof said by-pass chamber, said inlet opening and said second outlet opening, a filtration medium of relatively coarse, resilient, fibrous material occupying the interior of said filtering chamber, and means for bodily agitating said filtration medium.

'LIn a device of the character described, the

combination of a housing member composed of a spherical filtering chamber, inlet-and outlet 1 openings communicating with said chamber, a

and between said by-pass chamber leading between said firste named chamber and around said openings, at fil-. tration medium of relatively coarse, resilient, fibrous material occupying the, interior of said filtering chamber, means for oscillatingsaidfil-v tration medium with respect tosaid chamber, a second outlet opening positioned adjacentsaid inlet opening, and a three-way valve positioned at'the juncture of saidby-pass chamber, said inlet opening and said second outlet openinw 8. In a device of the character described, the combination of a chamber inlet and outletgopenr, ings communicating withsaid chamber, a-filtration'medium of relatively coarse, resilient, fibrous material occupying. the interior ofsaid 'chambox and forming a unitary mass throughwhich a grinding compound. may flow, a shaft journaled centrally of said chamber, one end of said shaft projecting exteriorly of said chamber, project.- ing' elements extending radially-of said shaft'for engaging with said filtration medium, and means for rotating said shaft, whereby different surfaces of said medium may be successively presented to the flow of said compound.

9. In a grinding process, the method of oceluding fine minute products of abrading action in a fluid grinding compound, removing. said products from said grinding compound by passing the latter through a filtration medium composed of relatively coarse fibrous resilient material, and then removing said products from said filtration medium by diverting the flow of said grinding compound through another filtration medium, reversing the flow of the resultant compound through said first named filtration medium and simultaneously moving the latter as a unit, whereby different surfacesthereof may be successively presented to the fiow of said compound.

10. In a device ofthe character described, a housing member composed of a filtering chamber, inlet and outlet openings communicating with said chamber, a filtration medium of relatively coarse, resilient fibrous material occupying the interior of said filtering chamber, a bypass chamber leading around said first-named V chamber and between said openings, a second outlet opening positioned adjacent said inlet opening, and a three-way valve positioned at the juncture of said by pass chamber, said inlet opening and said second outlet opening, a shaft journaled centrally of said chamber, one end of 'said shaft projecting exteriorly of said chamber, projecting elements extending radially of said shaft for engaging with said'filtration medium, and means for rotatingsaid shaft.

11. In a grinding compound purification process, the method of removing the fine minute suspended products of abrasion from said grinding compound by circulating said compound through a filtration medium composed of a relatively coarse, fibrous, resilient material, and then removing said products from'said filtration medium at intermittent intervals by reversing the flow of said compound while simultaneously moving said filtration medium as a unit, whereby different surfaces thereof may be successively presented to the flow of said compound.

- 12. In a grinding compound purification process, the method of removing the suspended products of abrasion from said compound, which comprises the steps of circulating said compound through a filtration medium, and then removing said products from said filtration medium by 15G bodily rotating said medium as a unit, cleaning said compound and reversely flowing said compound through said medium, whereby coated portions of the filtration medium are directly acted upon by said cleaned compound.

13. In a grinding compound purification process, the method of removing the suspended products oi abrasion from said compound, which comprises the steps of circulating said compound through a filtration medium, composed of a relatively coarse, fibrous, resilient material, whereby oneside of said material becomes coated with said products, and then exposing said coated side to a reverse .flow of a flushing fluid to remove said products from said filtration medium.

14. In a filter for purifying liquids contaminated with fine particles of suspension and flotation, the combination of a chamber, inlet and outlet openings in said chamber, a filtration medium of relatively coarse, resilient, fibrous material occupying the interior of said chamber and forming a unitary mass through which said liquid may flow, and means for bodily moving such filtration medium as a unit, whereby difierent surfaces thereof may be successively presented to the flow of said liquid.

15. In a filter for purifying liquids contaminated with fine particles of suspension and flotation, the combination of a spherical chamber, inlet and outlet openings in said chamber, a filtration medium of relatively coarse, resilient, fibrous material occupying the interior of said chamber and forming a unitary mass through which said liquid may flow, and means for oscillating said filtration medium with respect to said chamber as a unit, whereby different sur faces thereof may be successively presented to the fiow of said liquid.

. RUDOLPH A. WALTERS.

NIELS A. SORENSON. 

